Prefabricated Warehouse Large Span Steel Structure Insulated Metal Storage Steel Building Fire Resistant

A prefabricated steel structure warehouse is an engineered metal building system in which all primary and secondary structural members are designed, fabricated, and surface-treated in a controlled factory environment, then shipped to site as a complete knock-down (CKD) package for bolt-together assembly.

The result is a column-free storage building with clear spans up to 100 m, eave heights up to 20 m, and a verified 50-year design service life—delivered in a fraction of the time required by conventional reinforced-concrete construction.

The load-bearing framework consists of hot-rolled, welded H-section steel portal frames, fabricated using Q355B structural steel (minimum yield strength: 355 MPa; ultimate tensile strength: 490 MPa). The frame sections feature a variable-depth design along the direction of the roof beams (purlins), strategically concentrating steel material at the frame knees and the ridge—locations where bending moments are at their maximum.

Compared to constant-depth frames of equivalent span and load-bearing capacity, this variable-geometry design typically reduces the overall steel consumption of the frame by 12% to 18%.

All primary welds are executed by certified welders and are inspected via Ultrasonic Testing (UT) or Magnetic Particle Inspection (MPI) in accordance with applicable standards. Connections between frame columns and beams, as well as beam-to-beam connections, utilize Grade 8.8 high-strength friction-grip bolts (M20-M24; equivalent to ASTM A325 standards). This ensures that the connections maintain consistent clamping force and fatigue resistance throughout the entire service life of the structure.

The roof purlins and wall girts (wall beams) are fabricated from Q235B steel, cold-formed into C- or Z-shaped cross-sections (section height: 200-300 mm). The standard configuration employs a continuous-lap purlin system, which helps minimize deflection under concentrated loads and simplifies the on-site installation process.

The accompanying component kit also includes anti-sag rods and tie rods (channel steel bracing). For projects with exceptionally stringent thermal performance requirements, EPDM thermal break pads can be installed beneath the purlin clips to interrupt thermal bridging and prevent condensation within the building envelope system.

Standard roofing and wall cladding materials consist of 75mm-thick Polyisocyanurate (PIR) insulated sandwich panels, achieving an overall assembly thermal transmittance (U-value) of ≤ 0.35 W/m²*K. To address the specialized needs of cold chain logistics or food-grade storage facilities, the sandwich panel thickness can be increased to 100mm or 150mm, thereby further reducing the U-value to ≤ 0.18 W/m²*K.

For warehouse applications requiring controlled atmosphere environments or refrigerated storage, we also offer the option of incorporating a continuous vapor barrier layer.

The facing of the sandwich panels utilizes 0.5mm-thick pre-coated galvanized steel sheets, finished with a surface coating of either PVDF (Polyvinylidene Fluoride) or SMP (Silicon Modified Polyester). Standard testing demonstrates that these panels exhibit salt spray resistance exceeding 500 hours, making this envelope system highly suitable for coastal and high-humidity environments.

Prior to surface coating, all structural steel components undergo blast cleaning to remove rust, achieving a surface cleanliness standard of Sa 2.5. Subsequently, the components are treated with a dual-layer epoxy zinc-rich primer anti-corrosion system, ensuring a total dry film thickness of no less than 120 µm (comprising two layers of 60 µm each).

For structures situated in marine climates, chemical industrial zones, or high-humidity environments, we offer Hot-Dip Galvanizing (HDG) as an upgraded corrosion protection solution; this solution has been validated via salt spray testing to provide effective corrosion protection for over 1000 hours.

Each project undergoes a customized engineering design process based on specific parameters provided by the client, including wind speed, seismic intensity, roof snow loads, and floor live loads. Structural analysis is primarily conducted using STAAD.Pro or SAP2000 software.

Project design documents and drawings can be prepared in accordance with the following standards and codes:

• GB 50017 (Chinese National Code for Design of Steel Structures)
• EN 1993 - Eurocode 3 (European Standard)
• AISC 360 (American Institute of Steel Construction Standard)
• AS 4100 (Australian Standard)

For projects located in Australia, the United States, Canada, the United Kingdom, and South Africa, we can provide design drawings stamped and certified by a Registered Professional Engineer (PE) upon client request.

All orders are shipped as pre-drilled, bolt-connected component kits; each component is labeled and consolidated into 20-foot or 40-foot high-cube shipping containers. Every structural member is numbered and marked to correspond directly with the installation drawings, thereby eliminating the need for on-site cutting and reducing the reliance on skilled labor.

A typical 5,000-square-meter warehouse structure can be erected by a construction crew of just 15 people within 2 to 4 weeks—a construction speed that is 30% to 50% faster than that of a reinforced concrete structure of equivalent scale.

Every project comes standard with an illustrated installation manual, detailed connection node drawings, and online technical support services; on-site construction guidance services are also available upon request.

Given that all structural connections are secured via bolting rather than on-site welding, future longitudinal expansions do not require the demolition of existing end-wall structures. This feature ensures that your capital investment remains fully protected as your operational requirements grow.

Furthermore, at the end of the building's service life, the steel structural materials boast a recyclability rate of over 90%, fully aligning with the principles of the circular economy and the requirements of green building certification systems.

Our prefabricated steel warehouses are engineered and constructed worldwide, serving diverse industrial sectors including logistics, manufacturing, cold storage, and commercial distribution centers across multiple continents and climate zones.